This invention relates to an enantioselective process for producing hydroxy-alkyl substituted azetidinones useful as hypocholesterolemic agents, in particular for preparing 1-(4-fluorophenyl)-3(R)-[3(S)-hydroxy-3-(4-fluorophenyl)propyl)]-4(S)-(4-h ydroxyphenyl)-2-azetidinone, claimed in U.S. Pat. No. 5,767,115.
Processes for preparing the corresponding azetidinone without the 3-hydroxy substitutent are claimed in U.S. Pat. Nos. 5,728,827 and 5,561,227. Other processes for preparing 1-(4-fluorophenyl)-3(R)-[3(S)-hydroxy-3-(4-fluorophenyl)-propyl)]-4(S)-(4- hydroxyphenyl)-2-azetidinone are disclosed in U.S. Pat. Nos. 5,631,365 and 5,739,321.